More than a third of drivers in Tippecanoe County, Ind. believe driving 20 mph over the speed limit is OK, and the rest have no qualms going 5 to 10 mph over the limit, a Purdue University researcher has found.

Civil engineering professor Fred Mannering’s study of 988 drivers in the county where Purdue is located found few people respect speed limits and feel as though they’re still driving safely even when they exceed the legal standards.

“People really don’t respect speed limits like they did in the past,” said Mannering, whose research is being published in the journal Transportation Research Part F: Traffic Psychology and Behavior.

Matt Swisher of Lafayette said he isn’t going to hurt anyone by going a little over the posted limit, and driving at speeds of 85 or 90 mph on the highway is safe for him.

“If a road’s real curvy and I don’t know it, I don’t speed,” Swisher told the Journal & Courier of Lafayette. “I’m careful in school zones.”

Mannering said that while some people who speed are in a hurry, others don’t believe in the limits because they had been set low in the 1970s more for political reasons than safety.

The study also found that people tend to slow down if they know an area’s speed is tightly regulated, but speed up if they think there’s little chance they’ll get caught.

“If you’re driving 15 or 20 miles per hour over the speed limit and you don’t see any enforcement, you assume it’s safe,” Mannering said.

Tamara Jones of Lafayette lost her license because of speeding tickets. She drove a taxi and said driving fast was how she earned money.

But she also said she didn’t think anyone would get hurt if she drove fast.

“I was just going too fast,” said Jones, who said she now has her license back. “I’m a lead foot.”

Mannering’s study also found that some places set artificial speed limits that could add to the disregard for speed laws. For instance, if town officials know that it’s safe to go 45 mph on a road, they might set the speed limit at 35 mph so that when people speed, they aren’t going a dangerous speed.

The problem, Mannering said, is that some people might go the speed limit while others disregard it.

And when drivers realize that the artificial limit is too slow, they might believe all speed limits are too slow, causing them to speed in areas where the limit is set at the highest safe speed.

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